Antler-Inspired Prosthesis Breaches Skin Barrier

By Chuck Seegert, Ph.D.

Typically, people who wear prosthetic legs can only be active for a limited amount of time. Stumps often get sore where they interface with the prosthetic cup, requiring the patient to rest. A new method of implanting the prosthetic anchor, however, may make prosthetic use essentially unlimited.

Antler anatomy was the inspiration for the new biomimetic prosthetic attachment, according to a recent study published in the Journal of Anatomy. In the study, deer antler anatomy was characterized at the site where the antlers pass through the skin. Using this knowledge, the team then designed a titanium device that mimicked key features seen in the antlers. They call their device the ITAP, which is short for intraosseous transcutaneous amputation prosthesis.

In particular the ITAP device used in this study consisted of a bone screw that passes through both sides of the bone cortex. On one end of the screw was a flange that had been textured to mimic the porosity seen in the deer antler, a feature that allowed the skin to integrate with the implant.

ITAP implants have been tested clinically as well, according to a recent story by Health First Europe.

"It's like they've given me my leg back,” said Mark O’Leary, a 40 year old from south London, in the story. “I know that sounds a bit trite. With this thing I just click the stump on in the morning and I can walk as far as I like, do anything I want within reason. There's no limit."

Mark was one of the first 20 patients that participated in the study.

In addition to increasing the length of time an amputee can use a prosthesis, attaching directly to the bone has other distinct advantages.

"Just knowing where my foot is, my ability to know where it is improved dramatically because you can feel it through the bone. A textured road crossing, I can feel that. You essentially had no sensation with a socket and with Itap you can feel everything," Mark said in the story.

Crossing the barrier of the skin is a significant step forward for prosthetic technology. Other areas where researchers are focusing include neural control of robotic prostheses.

Image Credit: Journal of Anatomy